BEYOND TIME - FREQUENCY ANALYSIS : ENERGY DENSITIES IN ONE AND MANY DIMENSIONSRichard
نویسنده
چکیده
Given a unitary operator A representing a physical quantity of interest, we employ concepts from group representation theory to deene two natural signal energy densities for A. The rst is invariant to A and proves useful when the eeect of A is to be ignored; the second is covariant to A and measures the \A" content of signals. The construction is quite general and is also easily extended to the multi-operator case, which generalizes previously derived joint densities such as the time-frequency and timescale distributions.
منابع مشابه
Beyond Time - Frequency Analysis : Energy Densitiesin One and Many
| Given a unitary operator A representing a physical quantity of interest, we employ concepts from group representation theory to deene two natural signal energy densities for A. The rst is invariant to A and proves useful when the eeect of A is to be ignored; the second is covariant to A and measures the \A" content of signals. We also consider joint densities for multiple operators. In the pr...
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Given a unitary operator A representing a physical quantity of interest, we employ concepts from group representation theory to define two natural signal energy densities for A. The first is invariant to A and proves useful when the effect of A is to be ignored; the second is covariant to A and measures the “A” content of signals. We also consider joint densities for multiple operators and, in ...
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